However, there would also need to be an extended period of longitudinal analysis of the effects of the therapy on the experimental group mice's health to see if the improvement continued and did not produce damaging side effects. The MSCs in the liver therapy are not derived from human embryos and thus the objections to discarding human embryos are not a factor in the ethical discussion about the therapy. In fact, "the number of MSCs that can be obtained from a donor is significantly lower than the number needed for tissue regeneration. Therefore, MSCs are expanded ex-vivo in media supplemented with growth factors" and created in a lab ("MSC growth factors," R&D Systems, 2013). The main ethical objections to the use of MCSs revolve around the question of scientists' right to create new organs and the possible risks involved. The Japanese research team "relied on a 'cocktail' of so-called induced stem cells grown to resemble the nascent liver bud cells used in the experiment" (Vergano 2013). The mice in the experiment must be closely monitored to see if they develop liver tumors, one of the possible negative side effects of the therapy. "Concerns linger about cancer risks from stem cells implanted into patients. The liver buds also lacked immune cells that filter toxins from the bloodstream and structural cells that send digestive enzymes into the gut from a real liver" (Vergano 2013). Other objections which might arise are the fact that liver transplants are effective, proven therapies while this therapy is not.

If successful, the therapy could free many people waiting for a liver donor of a long and painful wait...

As is the case with most novel therapies, there will be a gradual transition to the therapy in a wider and wider range of patients, and patients must understand the risks of participation. Liver transplant may still be more suitable for many patients, but this therapy offers a viable alternative.
Given the seriousness of liver failure and the problems of availability and acceptability of transplants, exploring this stem cell therapy seems to be a potentially life-enhancing prospect for many patients. However, since the actual type of regenerative therapy that would be used has not been perfected and the risks are not fully understood, caution is essential in proclaiming the therapy's merits.

Works Cited

"Mesenchymal stem cells (MSCs)." R&D Systems. [7 Jul 2013]

http://www.rndsystems.com/molecule_group.aspx?g=805&r=7

"Mesenchymal stem cells (MSCs) growth factors." R&D Systems. [7 Jul 2013]

http://www.rndsystems.com/molecule_group.aspx?g=818&r=7&g2=805

"Researchers create miniature human liver out of stem cells." CBS. 203 [7 Jul 2013]

http://www.cbsnews.com/8301-204_162-57592325/researchers-create-miniature-human-liver-out-of-stem-cells/

Vergano, D. "Stem cells help grow human liver tissue 'buds' in mice." USA Today. 3 Jul 2013.

[7 Jul 2013] http://www.usatoday.com/story/tech/sciencefair/2013/07/03/liver-buds-stem-cell/2486013/